This invention relates to a steering system for a marine propulsion unit and more particularly to an improved remote steering operator for a marine outboard drive.
Generally marine outboard drives include a propulsion unit that is mounted for steering movement about a generally vertically extending axis in some form of steering or swivel bracket. The steering or swivel bracket is, itself, mounted for pivotal movement about a horizontally extending trim axis by a clamping bracket or other device that is affixed to the transom of a watercraft. The propulsion unit has affixed to it a steering arm which extends forwardly and frequently across the transom for steering of the propulsion unit.
There are many times when it is desirable to steer the propulsion unit from a position remote from the transom, for example by a forwardly positioned steering wheel. To accomplish this movement, there is normally provided a flexible transmitter that is driven by the steering wheel and which extends rearwardly and is connected to the steering bracket or steering arm for steering of the propulsion unit. With this type of system, the flexible cable is generally connected to a member that is slidably supported in a tubular member which is disposed concentrically and telescoped with the tilt axis of the swivel bracket. Frequently hydraulic power assists are employed which also include a hydraulically operated cylinder and actuating valve mechanism which are interconnected with the cable and the steering arm for hydraulic assist of the steering.
There are a number of disadvantages with the type of construction previously used. In the first instance, when the cable actuated member is positioned concentrically with the tilt axis, this type of construction has a number of problems. Since the support for the cable end also defines the tilt axis, it must be made strong enough to sustain propulsion forces and forces which are encountered when underwater obstacles are struck. Also, the unit is disposed so that it will be in proximity to the transom and hence, must be formed from a corrosion resistant material. Thus, the costs of the cable support become excessive. In addition, since the cable guide forms a portion of the propulsion unit, it is not possible to form a separate subassembly and there are difficulties in ensuring accurate assembly. These disadvantages are further multiplied when a hydraulic assist for the steering is provided.
It is, therefore, a principal object of this invention to provide an improved and simplified steering mechanism for a boat propulsion unit.
It is a further object of this invention to provide a steering mechanism for a boat propulsion unit which can be formed as a separate assembly from the propulsion unit.
It is a further object of this invention to provide an improved power assisted steering mechanism for a marine propulsion unit.
It is a further object of this invention to provide a hydraulic steering mechanism for a marine propulsion unit which can be made as a separate assembly.